Nibbling machine



Nov. 20, 1928. 1,691,928

G. N. HUTCHINSON El AL NIBBLING MACHINE Filed Jan. 1925 2 Sheets-Sheet 1 Nova 20, 1928.

G. N. HUTCHINSON ET AL NIBBLING MACHINE Filed Jan. 1925 2 Sheets-Sheet agivemtog Y Y I Patented'Nov. 20, 1928.

'4 1,691,928 PATENT. OFFICE.

' GLEN N. nu'rcmNsomor MONTCLAIR, NEW JERSEY, AND any s. GARDEN, or ENDI- cor'r, NEW YORK, ASSIGNORS r INTERNATIONAL TIME RRcoRmNe COMPANY OF/NEW YORK, or ENDIGOTT, Nnw YORK,,A CORPORATION or NEW YORK.

NIRR ING mAcnINR. 7

Application filed January 6, 1925. Serial No. 780.

T it down, reaching into the die on each downward strike. The work is fed slowly over the die, and the unch in cooperation with the die, shears oil 0 ips. Inasmuch as the work 1s erformed on one side only of the punch, there 1s a constant tendenc for the punch to pushed back out of a ignment with the die,- and frequently, the rear ed e of the punch strikes the rear edge of the ie. This causes the punch to break, and often also destroys the. die.

One of the objects of the present invention is to overcome thi'sfault, b devising a punch that will be positively gui ed into the die, so that it cannot be forced over the edge thereof.

These machines are also provided with a stripper for preventing the metal being cut from being lifted by the unch. This stripper is adjustable up and own, as 1s also the punch holder. Workmen frequently ad ust the punch holder to adjust the stroke of the unch, without adjusting the stripper accordmgly. If the punch holder is lowered, without lowering the stripper, the holder, when the machine starts to operate, strikes the top 36 of the stripper and breaks it off.

Another object of the invention is to devise a stripper that cannot be broken or otherwlse damaged when the operator fails to properly adjust it;

Referring to the drawings wherein we have shown what we now consider to be the preferred form of our invention:

Fig. 1 is a side elevation ofthe upper position ofa nibbling machine, partly in section. Fig. 2 is a front elevation of the same portion of the machine, partly in section.

Fig. 3 is a section taken on line 3-3 of Fig. 2.

Fig. 4 is a detail of the punch and die.

In the drawings, the table or bed plate is shown at 1, fastened by bolt 2 to the block 3 which is in turn fastened by bolts 4 to the bed 5 of the machine. The die 6 is held in position in the block 3. The overhanging arm-7 carries the punch holder 8, adjustably fastened by screw threads to a plunger 9, adapted to be reciprocated u and down by a drive shaft-.10. The drive f rms no part of the present invention, and is therefore not shown here. The punch 11 is fastened in a bushing 12 in the holderS. The punch extends downwardly as at 13 (Fig. 4) below its cutting edge 14, and the back surface thereof engages the rear interior of the die. The depending portion13 of thepunch may be long enough so as not to rise entirely out of the die when the punch is in its raised position, or if it is permitted to rise out of the die, it should at least be long enough to enter the die before the cutting shoulder 14 reaches the metal which is being cut. This cooperation between the punch and die while the cutting or punchinfi is being done, serves to guide the punch, an prevents it from working back or being pushed back to strike the edge of the die. The sheet 15 of metal may be pushed against the forward art of the depending portion 13 of the punc which will thus act as a guide in feeding the sheet to the machine.

The stripper is shown in the form of an inverted cap 16, having threaded engagement with the inner circumference of a bushing 17. The lower part of the arm 7 is bored slightly larger than its main interior diameter, to receive the bushing 17. Reaching into this portion of the bore are spring-pressed steel balls 18, contained in the walls of the bore. The holes through which the balls reach are smaller toward the inside or toward the bore than the diameter of the balls, so that the latter cannot fall through. The outer circumference of the bushing 17 is rovided with a circumferential groove 19 an numerous vertical flutings 20. Thus, when the bushing 17 is slipped into place, the balls 18 will engage it in the groove 19 and hold it up in position. The halls will also nestle in the flutings 20 and prevent jarring of the machine from causing the bushing to turn. The stripper 16 has an arm 21 rigidly fixed thereto, reaching into a groove 22 in a member 23, supported for upand down adjustment in arm 7. The screw 24 is adapted to lock this member in position. This arrangement prevents the stripper from turning too freely in the bushing 17. Up and down adjustment of the stripper may be effected by turning the bushing around and thus causihg the stripper to be screwed up and down therein. The punch reaches through a hole in the bottom of the stripper.

If the punch holder 8 should be adjusted without a corresponding adjustment of the stripper being made, and the holder strikes ent is:

' reciprocating punc the stripper in consequence, the springpressed balls 18 will permit the bushing 17 to e pushed down out of position with the.

stri per, and none of the parts will be damag I Having described our invention, what we claim and desire to secure by 'Letters Pat- 1. In a punching machine, a reciprocating punch holder, a work stripper and means for releasably mounting said stripper adjacent to said holder to permit it to be released when engaged by the holder.

2. In a punchin machine, 'a support, a holder associated with said support, a work stripper releasably attached to said support and adapted to be detached therefrom when struck by said holder.

3. In a punchin machine, a support, a reciprocatingpuncfi holder associated with said support, a member yieldably attached to said support, and a work stripper attached to said member and adapted to be adjusted by relative rotation of the member and stripper 4. n a punching machine, a support, a

reciprocating punch mechanism mounted on said support, a stripper, means for mounting said stripper adjacent said punch mechanism said means comprising yieldable" members for engaging said stripper to hold it in place but permit it to be detached when struck by the punch mechanism.

5. In a punching machine, a support, a

reciprocating punch mechanism mounted, on

said support, stripping mechanism comprising a threaded member and a stripper having a threaded portion coacting therewith, means for mounting said mechanism on said support comprising yielding members for en; gaging said member to hold it in place'but to release it when struck by any portion of member. H i

6. In a punching machine, a support, a

struck by said mechanism.

7. In a punching machine, a support, a re- 1' ciprocating punch mechanism mounted there on, a work stripper and means for impos1-" tively securing it on said support adjacent stripper with respect to saidsupport.

mit it to be detached from said sup-portfif 9 a said reciprocating mechanism to permit it to be detached from the support when struck by f said mechanism and means for adjusting said In testimony whereof we'here'to aflix our 7 signatures.

GUY s. GARDEN.

GLEN N. HUToHmsou 

